The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 29, 2019
Filed:
Mar. 02, 2016
Canon Kabushiki Kaisha, Tokyo, JP;
Takumi Uehara, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A light amount adjusting device includes ND filters rotating around shafts serving as rotation shafts and moving between in-use positions and retracted positions, arranged on a base plate. The respective ND filters include uniform density portions, gradation portions, and transparent portions. If the ND filters are in the retracted positions, the transparent portions of the respective ND filters overlap in an area facing an aperture to cover the entire aperture with the transparent portions. If the ND filters are in the in-use positions, the gradation portions of the respective ND filters overlap in an area facing the aperture to cover the entire aperture with the gradation portions and the uniform density portions. Moreover, a combined density acquired when the gradation portions overlap in just proportion is substantially the same as an optical density of each of the uniform density portions.